package com.changgou.search.service.impl;

import com.alibaba.fastjson.JSON;
import com.changgou.search.pojo.SkuInfo;
import com.changgou.search.service.SearchService;
import org.apache.commons.lang.StringUtils;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.Operator;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.bucket.terms.StringTerms;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.elasticsearch.search.sort.SortBuilders;
import org.elasticsearch.search.sort.SortOrder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.PageRequest;
import org.springframework.data.domain.Pageable;
import org.springframework.data.elasticsearch.core.ElasticsearchTemplate;
import org.springframework.data.elasticsearch.core.SearchResultMapper;
import org.springframework.data.elasticsearch.core.aggregation.AggregatedPage;
import org.springframework.data.elasticsearch.core.aggregation.impl.AggregatedPageImpl;
import org.springframework.data.elasticsearch.core.query.NativeSearchQueryBuilder;
import org.springframework.stereotype.Service;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

@Service
public class SearchServiceImpl implements SearchService {

    @Autowired
    private ElasticsearchTemplate elasticsearchTemplate;   //默认具有分页效果10条

    //设置每页查询数据
    private static final Integer PAGE_SIZE = 20;

    @Override
    public Map search(Map<String, String> searchMap) throws Exception {

        Map<String, Object> resultMap = new HashMap<>();

        if (searchMap != null) {
            //构建查询条件封装对象
            NativeSearchQueryBuilder nativeSearchQueryBuilder = new NativeSearchQueryBuilder();
            BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();

            //按照关键字进行查询
            if (StringUtils.isNotEmpty(searchMap.get("keywords"))) {
                boolQuery.must(QueryBuilders.matchQuery("name", searchMap.get("keywords")).operator(Operator.AND));
            }

            //按照品牌进行过滤查询
            if (StringUtils.isNotEmpty(searchMap.get("brand"))) {
                boolQuery.filter(QueryBuilders.termQuery("brandName", searchMap.get("brand")));
            }

            //按照规格进行过滤查询 /search?keywords=手机&spec_网络=移动4G
            for(String key : searchMap.keySet()){
                if(key.startsWith("spec_")){
                    String value = searchMap.get(key).replace("%2B", "+");
                    //spec_网络制式
                    boolQuery.filter(QueryBuilders.termQuery(("specMap."+key.substring(5)+".keyword"),value));
                }
            }

            //按照价格进行区间价格过滤查询
            if(StringUtils.isNotEmpty(searchMap.get("price"))){
                String[] prices = searchMap.get("price").split("-");
                //0-500 500-1000
                if(prices.length == 2){
                    boolQuery.filter(QueryBuilders.rangeQuery("price").lte(prices[1]));
                }
                boolQuery.filter(QueryBuilders.rangeQuery("price").gte(prices[0]));
            }

            nativeSearchQueryBuilder.withQuery(boolQuery);

            //按照品牌进行分组（聚合）查询
            String skuBrand = "skuBrand";
            nativeSearchQueryBuilder.addAggregation(AggregationBuilders.terms(skuBrand).field("brandName"));

            //按照规格进行聚合查询实现
            String skuSpec = "skuSpec";
            nativeSearchQueryBuilder.addAggregation(AggregationBuilders.terms(skuSpec).field("spec.keyword"));

            //开启分页查询
            String pageNum = searchMap.get("pageNum"); //当前页
            String pageSize = searchMap.get("pageSize"); //每页显示多少条数据
            if (StringUtils.isEmpty(pageNum)) {
                pageNum = "1";
            }
            if (StringUtils.isEmpty(pageSize)) {
                pageSize = PAGE_SIZE + "";
            }
            //设置分页参数
            //第一个参数：当前页，是从0开始  第二个参数：每页显示多少条数据
            nativeSearchQueryBuilder.withPageable(PageRequest.of(Integer.parseInt(pageNum) - 1, Integer.parseInt(pageSize)));

            //按照相关字段进行排序查询
            //1.当前域 2.当前的排序操作（升序还是降序）
            if (StringUtils.isNotEmpty(searchMap.get("sortField")) && StringUtils.isNotEmpty(searchMap.get("sortRule"))) {
                if("ASC".equals(searchMap.get("sortRule"))){
                    //升序
                    nativeSearchQueryBuilder.withSort(SortBuilders.fieldSort((searchMap.get("sortField"))).order(SortOrder.ASC));
                }else{
                    //降序
                    nativeSearchQueryBuilder.withSort(SortBuilders.fieldSort((searchMap.get("sortField"))).order(SortOrder.DESC));
                }
            }

            //设置高亮域以及高亮样式
            HighlightBuilder.Field field = new HighlightBuilder.Field("name")  //高亮域
                    .preTags("<span style='color:red'>")  //高亮样式前缀
                    .postTags("</span");  //高亮样式后缀
            nativeSearchQueryBuilder.withHighlightFields(field);

            //开启查询
            /**
             * 第一个参数：条件构建对象
             * 第二个参数：查询操作实体类
             * 第三个参数：查询结果操作对象
             */
            //封装查询结果
            AggregatedPage<SkuInfo> resultInfo = elasticsearchTemplate.queryForPage(nativeSearchQueryBuilder.build(), SkuInfo.class, new SearchResultMapper() {
                @Override
                public <T> AggregatedPage<T> mapResults(SearchResponse searchResponse, Class<T> aClass, Pageable pageable) {
                    //查询结果操作
                    List<T> list = new ArrayList<>();
                    //获取查询命中结果数据
                    SearchHits hits = searchResponse.getHits();
                    if (hits != null) {
                        //有查询结果
                        for (SearchHit hit : hits) {
                            //SearchHit 转换为skuInfo
                            SkuInfo skuInfo = JSON.parseObject(hit.getSourceAsString(), SkuInfo.class);
                            //进行高亮提换
                            Map<String, HighlightField> highlightFields = hit.getHighlightFields();
                            if(highlightFields != null && highlightFields.size() > 0){
                                //替换数据
                                skuInfo.setName(highlightFields.get("name").getFragments()[0].toString());
                            }

                            list.add((T) skuInfo);
                        }
                    }
                    return new AggregatedPageImpl<T>(list, pageable, hits.getTotalHits(), searchResponse.getAggregations());
                }
            });
            //封装最终的返回结果
            //总记录数
            resultMap.put("total", resultInfo.getTotalElements());
            //总页数
            resultMap.put("totalPages", resultInfo.getTotalPages());
            //数据集合
            resultMap.put("rows", resultInfo.getContent());
            //封装品牌的分组结果
            StringTerms brandTerms = (StringTerms) resultInfo.getAggregation(skuBrand);
            List<String> brandList = brandTerms
                    .getBuckets()
                    .stream()
                    .map(bucket -> bucket.getKeyAsString())
                    .collect(Collectors.toList());
            resultMap.put("brandList", brandList);

            //封装规格分组结果
            StringTerms specTerms = (StringTerms) resultInfo.getAggregation(skuSpec);
            List<String> specList = specTerms
                    .getBuckets()
                    .stream()
                    .map(bucket -> bucket.getKeyAsString())
                    .collect(Collectors.toList());
            resultMap.put("specList", specList);

            //设置当前页
            resultMap.put("pageNum", pageNum);

            return resultMap;
        }

        return null;
    }
}
